Color Shifts between PNG files exported from FCP in Photoshop and Preview? Which software can I trust?

[Matthew Taylor]

screenshot2012-06-22at13.56.39.png

[Steve Eisen]

[Matthew Taylor] “I cannot find a solution to this anywhere. Can anyone point me in the direction of a tutorial about setting up my IMac so all this software can communicate? Or offer any advice, its so frustrating.”

I will point you in the right direction. See if you can figure it out. Hint:Computer display and Video display are different.

https://library.creativecow.net/articles/ross_shane/fcp_faq.php

Steve Eisen
Eisen Video Productions
Vice President
Chicago Creative Pro Users Group

[Matthew Taylor]

Hello Steve

I appreciate your response, but could you offer me any less cryptic help? I have read the 3 FCP FAQs you linked to and none of the fifty hints points to this issue.

I am understanding from reading around forums that the monitor display and the video displays are different. But can’t find the missing link. Is it FCP itself that works in a single ‘color space/profile’ or is color profile dependent on codec?

I am working in ProRes 422, but I am assuming when exporting a PNG, the codec bears no relation to the color profile in Photoshop? Once again I’m stumped.

And again, any help from anyone would be greatly appreciated.

Regards

Matt Taylor

[Jeff Meyer]

The issue is video streams use a different color space, and it doesn’t properly display on a computer monitor. You can calibrate your computer monitor til the cows come home but they won’t be the same. Note that Adobe RGB and sRGB are both RGB color spaces with values for red, green, and blue. Video color spaces (Rec. 601 for SD and Rec. 709 for HD) are YUV, or a luminance channel, then channels carrying the deltas for red and blue. This may seem like a silly arrangement, but it was rather brilliant when it was devised as it allowed a seamless transition from b/w broadcasting to color broadcasting.

To answer your question, you can’t trust the display in Photoshop or Final Cut for video work, but you can trust an external monitor that goes through an IO box. The IO box gives you an output from Final Cut in the YUV color space. Plugging an HDMI monitor into a Mini-DisplayPort or Thunderbolt port doesn’t count because you’re working in RGB at that point.

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One thing that might be helpful is checking your gamma interpretation. Excerpt from the FCP manual:

To change the Gamma Level property of a clip in the Item Properties window
Select a clip in the Browser or in a sequence.

Choose Edit > Item Properties > Format (or press Command-9).

Do one of the following:

Control-click the value next to the Gamma Level property, then choose a predefined gamma value for the clip (Source, 1.8, or 2.2) from the shortcut menu.

Click in the Gamma Level field and enter a gamma value or type “Source,” then press Enter.

Tip: To see how a clip’s gamma affects its brightness, try changing the Gamma Level property of a clip while viewing the clip in the Viewer or Canvas.

( https://documentation.apple.com/en/finalcutpro/usermanual/index.html#chapter=85%26section=8%26tasks=true )

[Matthew Taylor]

Hi Jeff

Thanks so much for your detailed reply, It has helped in some ways to explain the problem. I am fully aware I need to grade/colour correct through a broadcast monitor, but I don’t often work for broadcast and work more in the corporate sector, where the main distribution is web anyway, and also money is tight at the mo.

Coming from a Premiere background, I just find this whole issue such an oddity, In Premiere I could export my still to Photoshop, it would open with exactly the same colour space, do whatever work I wanted to do with it, then bring it straight back to Premiere, again with the correct colour space. It used to be a doddle.

It now seems impossible to work the way I used to between FCP and Photoshop. Even with a broadcast monitor I am pretty sure I wouldn’t be able to view my still image export in Photoshop on the monitor. Would I? Its not something I have ever been aware of in the past.

The issue I have is that everything looks different between applications on the same monitor…Something that never used to be an issue with Premiere and Photshop on a PC. Perhaps its time to finally make that switch back to Adobe….

I really do appreciate your advice, its just not the help am looking for unfortunately. I would just like a solution to everything looking as it should on the same monitor. But seemingly this is an impossibility

Regards

Matt Taylor

[Matthew Taylor]

Hello Again Jeff

Also just tried your advice on changing the Gamma in the item properties, but CTRL clicking gives me no option, as you can see from this screenshot there is no option to change Gamma levels.

screenshot2012-06-23at13.28.16.png

Once again stumped, it really can’t be this difficult can it? (Reaches for Adobe Production Premium)

Regards

Matt Taylor

[Matthew Taylor]

Hello Everyone again

Seems I am talking to myself on this again as no-one has a definitive answer. My question now is, that If FCP cannot output a PNG file to Photoshop with the same colors as the timeline. How is it that I can create a PNG from scratch in Photoshop, bring it to FCP and the colours are fine, as in, displaying in FCP exactly as they did in Photoshop. Its only on the reverse…exporting from FCP to Photoshop that these strange color artefacts appear.

Please, if there is anybody with a response to this I’m seriously considering a financial reward. Its just so frustrating.

Any responses that mention broadcast monitors, will owe me a financial reward. You have been warned.

Regards

Matt Taylor

[Todd Bunner]

Hi Matthew,
I have found that FCP has all sorts of anomalies when dealing with color space, whether 24-bit RGB, or YUV and color space turned off. My best bet in all my years, was to trust Adobe After Effects when dealing with video projects for exporting photos to video to ensure no gamma shifting on multiple jobs/projects. People will give you all kinds of lines about what to follow, but remember software is not infallible, I’ve learned that over the years. I remember once where Adobe CS4 had a slight gamma shift to white when using ‘save for web’ when exporting a .png, and yet if you had done a normal ‘save as’, it would be correct.